1. Field of the Invention
The present invention relates to a command transmitting apparatus for transmitting a command which varies according to a mode to a content reproducing apparatus when the same key is operated by the user.
2. Description of the Related Art
In recent years, a portable player (content reproducing apparatus) having an HDD (hard disk drive) and a memory capable of storing a plurality of pieces of music piece data is being spread. A portable player is used to reproduce music piece data mainly outdoors. As an audio device used indoors, an amplifier such as a mini component system or radio-cassette player is used. Recently, an amplifier having a connector for connecting a portable player appears. In the case of using a portable player indoors, the portable player is connected to the connector of the amplifier disposed indoors, music piece data reproduced by the portable player is amplified by the amplifier, and sound is reproduced from a speaker connected to the amplifier.
The amplifier has the function of transmitting/receiving a command to/from the connected portable player, and can control the portable player by using a system remote controller of the amplifier (remote controller transmitter). For example, when a reproducing command for reproducing the portable player is input to the amplifier by operation of the remote controller of the user, the amplifier transmits the reproducing command to the portable player. The portable player starts reproducing of the music piece data in response to a reproducing command received from the amplifier.
Such a content reproducing system has the following problems. In the case of realizing all of the controls of the portable player by a system remote controller of the amplifier, the system remote controller of the amplifier has to be provided with a number of operation buttons. As a result, problems occur such that the size of the system remote controller becomes large, and the cost increases.
For example, the portable player has a hierarchical menu screen for performing various settings of the portable player and selecting desired music piece data. To operate the hierarchical menu screen by the system remote controller of the amplifier, a cursor-up key and a cursor-down key for vertically moving a cursor indicating an item presently selected in the hierarchical menu screen are necessary. However, the cursor-up key and the cursor-down key are low-use-frequency keys used only in the hierarchical menu screen of the portable player. Therefore, a technique is demanded, for operating the hierarchical menu screen of the portable player by the system remote controller without providing the system remote controller with such low-use-frequency keys.
Japanese Unexamined Patent Application Publication No. 2006-244607 and Japanese Patent No. 3,894,226 disclose a content reproducing system having a portable player 11, a charger 12, and an amplifier 13. The portable player 11 is connected to the charger 12 via connectors for sound and communication. The charger 12 is connected to the amplifier 13 via a cable for sound (and for communication as necessary). The charger 12 transmits an instruction to reproduce a music piece selected by the user to the portable player 11. The portable player 11 receives the reproducing instruction, reproduces the specified music piece, and transmits a sound signal to the charger 12. The charger 12 transmits the sound signal received from the portable player 11 to the amplifier 13. The amplifier 13 amplifies the sound signal received from the charger 12 and reproduces music via a not-shown speaker. In such a content reproducing system as well, problems similar to the above occur.